[BE-61] Implement Stellar asset registration and on-chain transfer via assetsup contract

[yusuftomilola]

Overview

When an asset is created in AssetsUp, it can optionally be registered on the Stellar blockchain via the assetsup contract, creating an immutable on-chain record. Transfers can also be recorded on-chain. This gives the asset an on-chain identity that cannot be altered or deleted.

Context

• Depends on BE-60 (StellarService)
• The assetsup contract (contracts/assetsup/src/lib.rs) exposes a register_asset function — review its parameters before implementing
• On-chain registration should be optional (not every organisation needs blockchain anchoring)
• Add stellarAssetId, stellarTxHash fields to Asset entity (from BE-19) to track the on-chain ID

Acceptance Criteria

• POST /stellar/assets/register body: { assetId: string } (internal asset UUID) — calls register_asset on the Soroban contract with the asset metadata hash, stores returned stellarAssetId and stellarTxHash on the Asset record
• POST /stellar/assets/:id/transfer body: { toAddress: string } — calls the contract's transfer function, records the Stellar txHash on the AssetHistory entry
• GET /stellar/assets/:id — queries on-chain state for the asset (owner, registration timestamp, transfer count)
• Both endpoints return 409 Conflict if the asset is already registered on-chain
• Add stellarAssetId (nullable string) and stellarTxHash (nullable string) to Asset entity migration

[devcarole]

@devcarole has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hello, I would like to work on this issue

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[Nwoyemartha]

@Nwoyemartha has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Please I would like to work on this issue.

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[RUKAYAT-CODER]

@RUKAYAT-CODER has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi, am a full stack developer. can i take up this task?

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